Barack Obama and Mitt Romney prepare to go head to head in the first debate

Left: US First Lady Michelle Obama waves to supporters on the first day of the Democratic National Convention at the Time Warner Cable Arena in Charlotte, North Carolina, on September 4, 2012. Right: US Republican presidential candidate Mitt Romney's wife Ann waves to the crowd of supporters during the Republican National Convention at the Tampa Bay Times Forum in Tampa, Florida, on August 28, 2012.Picture: Stan HONDA-/AFP/GettyImages